Method of and machine for edging pile fabrics



June 5, 1934. MAlER 1,961,979

METHOD OF AND MACHINE FOR EDGING PILE FABRICS Filed May 26, 1932 2 Sheets-Sheet l Zhwentor 1 -Januaz mwwm attorneys June 5, 1934. MAIER 1,961,979

METHOD OF AND MACHINE FOR EDGING FILE FABRICS Filed Kay 26, 1932 2 Sheets-She'et 2 }W Snuentor 8g @LWMW (Ittorneg Patented June 5, 1934 UNITED STATES PATENT OFFICE METHOD OF AND MACHINE FOR EDGING PILE FABRICS Karl Maier, Stuttgart, Germany, assignor to Union Special Maschinenfabrik G. in. b. H., of

Stuttgart, Germany 7 Claims.

The invention relates to new and useful improvements in a method of and machine for edging pile fabrics to prevent the raveling of a cut edge of the fabric.

An object of the invention is to provide a method of edging pile fabric whereby the edge of the base fabric supporting the pile is covered by stitching threads, while the pile projecting from the base fabric is erect and undisturbed all the way to the edge of the fabric.

A further object of the invention is to provide a machine for passing thread loops between the pile and along the upper face of a base fabric at the edge portion thereof and thence through the fabric and locking said loops by other thread loops which extend about and cover the edge of the base fabric. I

In the drawings- Figure 1 is a view partly in front elevation and partly in section showing a machine embodying the means for carrying out the improved method;

Fig. 2 is a view partly in section and partly in plan of the structure shown in Fig. 1;

Fig. 3 is a view showing more or less diagrammatically and in side elevation the means for guiding the upturned edge portion of a fabric section, the stitch finger around which the stitches are formed, and the means for guiding a tape along the edge of the base fabric to aid in covering said edge, and

Fig. 4 is a perspective view of a pile fabric showing the position of said edgeportion during stitching, and the covering for the edge formed on the machine.

The invention is directed to a method of and machine for edging pile fabric, and more particularly a pile fabric consisting of a fabric base having projecting threads extending upright and substantially at right angles to the fabric base. When a fabric of this type is cut, it is likely to ravel, and the purpose of the invention is to provide an edging for the base fabric which will prevent the raveling thereof, and which at the same time, is so constructed as not to interfere with the erect pile extending from the base fabric all the way to the edge thereof. It has been a common expedient to provide the edge of a fabric with overedgestitches for covering and for preventing the same from raveling. When stitches of this character are applied to a pile fabric, as heretofore practiced, the pile is encircled by the stitches and broken down so as to lie fiat against the base fabric. By my improved method, the stitches which cover the edge of the base fabric and prevent the raveling thereof do not disturb, in'any way, the erect position of the pile in the region where the fabric section is encircled. In order to avoid the tying down of the pile threads, the thread loops are passed between the pile threads and along the face of the base fabric for a distance inward from the edge where said loops penetrate the base fabric. These loops as they emerge from the base fabric on the lower face thereof are e11- chained by other loops which extend about the edge of the fabric andcover the same. The edge covering loops are in turn locked by the loops which are inserted between the pile.

It is thought that the method and the edge covering produced thereby will be better understood by a description of the illustrated embodiment of a machine for carrying out the same. The machine for carrying out the method is preferably what is known as a flat bed type of sewing machine, consisting of a work support 1 above which is an overhanging arm 2 carrying a needle bar 3 which is provided with a needle 4. Cooperating with the needle beneath the work support is a thread. carrying looper 5 which enters the needle thread loops, and cooperating with the thread carrying looper 5 is an overedge thread carrying looper 6 which passes a loop of thread through the looper thread loop and positions its loop for the needle to enter. This is the ordinary way of making a three-thread overedge stitch, and. further description of the mechanism for forming such stitch is not thought necessary.

The material to be stitched is a pile fabric consisting of a base fabric 7 from which pile threads 8 project. This pile fabric is of a wellknown construction and is only illustrated diagrammatically in the drawings. The base fabric consists of warp and weft threads into which is woven the pile threads. The pile fabric with the pile on the upper face thereof, is fed into the sewing machine and to the stitching mechanism by a feed dog 9 which is of the usual construction and operates through slots 10 in the throat plate carried by the work support 1. The material is held on the work support by a presser foot 11 carried by the presser bar 12 which is also of the usual construction. Mounted on the work support is an edge guide 13 which is provided with 'a-vertical face 14. This edge guide is mounted on a shank 15 which is secured to the work support by a bolt 16 passing through an elongated slot in the shank, so that the edge guide may be adjusted to: various set positions relative to the line of feed. The fabric section is bent upwardly as indicated at 8 and passed along the face 14 of the edge guide, resting firmly against said face.

The fabric is held in this position and allowed to move along the edge guide by a presser roller 17 mounted for rotation on a bracket 18 carried by an arm 19 which is attached to a shank 20. The shank 20 is provided with an elongated slot, and the bolt 16 passes through this slot in the shank 20 and secures the same in different set positions, as well as the edge guide. This guide roller 1'7 rotates in a plane inclined to the work support and engages the fabric section at the fold or bend therein, and is the means which serves to hold the edge portion of the fabric section firmly against .he guiding face 14, and at the same time permits said upturned edge portion to freely pass along the edge guide and to the stitching mechanism.

When the edge portion is turned upward to a vertical position, the projecting pile threads are substantially horizontally arranged. The needle 4 passes down between the pile threads and along the upper face of the base fabric, entering the base fabric just beyond the bend or fold therein, as clearly shown in Fig. 1. The looper I 5 passes through the needle thread loop, and

then the looper 6 passes through the looper thread loop and to a position over the edge of the base fabric where the needle enters the loop of thread carried by the looper 6.

The stitch formed by the mechanism described above is shown in detail in Fig. 4. The needle thread is indicated at 21. This thread is formed into a series of loops, one of which is indicated at 22. The thread of the looper 5 is indicated at 23. This looper thread 23 is formed into a series of loops, and each loop is passed through a needle thread loop 22. The thread of the looper 6 is indicated at 24 and this thread is formed into a series of loops, and each loop is passed through one of the loops formed in the looper thread 23. Each loop formed in the looper thread 24 is so positioned that the needle on its descent passes through the loop in said looper thread 24, and thus it is that the loop 22 in the needle thread is passed through the loop of the looper thread 24, and is then locked by the loop formed in the looper thread 23, and the loop formed in the looper thread 23 is in turn locked by the loops formed in the looper thread 24. The thread loops are so drawn that the thread loops in the looper thread 24 overlie and cover the edge of the fabric base. The needle thread lies along the baseof the pile and the loops therein pass between the pile threads and along the upper face of the base of the fabric so that said needle thread loops do not bend over or fold down the projecting pile. The projecting pile threads are erect and substantially at right angles to the base fabric all the way to the edge thereof. As a result. the fabric is provided with an edge covering which prevents raveling of the base fabric, while the pile is undisturbed all the way to the edge of the fabric.

The edge guide 13 terminates in a stitch finger 25 over which the thread loops are formed, the position of the needle being indicated by the broken line aa in Fig. 3. Attached to the upper face of the edge guide 13 is a gauge plate 26. Said gauge plate overlies the vertical face 14 of the edge guide, and limits the extent to which the fabric section is upturned. This insures that the needle will puncture the base fabric at a uniform distance back from the edge thereof, and the enchained thread loops will be of uniform size.

It is sometimes desirable to cover the cut edge of the base fabric with a tape as well as with enchained thread loops. The gauge plate 26 is provided with a tape guide tube 27 having a guiding passage which extends down through the gauge plate 26. A tape 28 is led through this tube 27 and is directed along the edge of the base fabric. The enchained thread loops encircle the tape as shown in Fig. 4.

From the above it will be apparent that a method has been provided for edging pile fabrics whereby the enchained thread loops which encircle and cover the cut edge of the base fabric do not bend or break down the pile, but extend between the pile threads along the upper face of the base fabric, and thence through the base fabric. The looper thread loops which lock the needle thread loops are carried about the edge of the fabric, thus covering the cut edge of the base fabric, and are locked by the needle thread loops before they pass between the pile threads, so that none of the interlocked thread loops overlie and tie down the pile threads. They stand erect or perpendicular to the base fabric all the way to the edge thereof.

The presser roller 17 has its edges serrated and tapered at the sides thereof so as to disturb the pile as little as possible. Whatever folding or pressing down of the pile may occur through engagement of the roller therewith will soon be restored to erect position, as the pile threads are not in any way tied down by the stitching threads. The edge guide with the gauge and stitch finger carried thereby together wiih the presser roller, may be readily adjusted to accommodate pile fabric of different thicknesses. The thread of the looper 6 which forms the loops covering the edge of the fabric may be heavier threads and may be similar in character and in color to the pile threads, while the needle thread and the under looper thread will be of the usual character. This will make a seam which is practically unnoticeable, and the carpet or pile fabric has the appearance as though the edge had never been cut and sewed. The stitch length is preferably made very short so as to more effectively cover the edge of the base fabric. When a heavy thread is used with a short stitch, the edge of the base fabric is completely protected against raveling, and is covered and concealed by the stitching threads. The cloth strip or tape when used also further aids in the concealing and protecting of the cut edge of the base fabric. When the tape is guided by the gauge member, it is laid right on the cut edge of the warp which prevents the warp threads from projecting out between the thread loops. No threads will appear on the top side of the rug or carpet, and a protected edge is provided which prevents the base fabric from raveling. Furthermore, by the improved method wherein the edge portion of the fabric section is upturned, the ordinary fiat bed overedge stitching mechanism may be readily reconstructed for carrying out the method.

While there has been shown a three-thread overedge stitch forming mechanism, from certain aspecs of the invention it is possible that a twothread overedge stitch forming mechanism might be used, the essential feature consisting in the passing of the needle thread loops between the pile threads and close to the upper face of the base fabric, and thence through the base fabric, and

that the locking loops which secure the needle thread loops shall pass around and cover the edge of the base fabric.

It is obvious that minor changes in the details of construction and the arrangement of parts in the apparatus described may be made without departing from the spirit of the invention as set forth in the appended, claims.

Having thus described the invention, what I claim as new and desire to secure by Letters- Patent, is--.,

1. The method of edging pile fabrics consisting in laying a needle thread along the base of the pile threads at the edge of the fabric and passing loops therein between the pile threads along the upper face of the base fabric and thence through the base fabric at a distance back from the edge thereof, and securing said ihread loops by other thread loops which extend over and cover the edge of the base fabric and are in turn secured by the first-named thread loops which are passed between the pile threads.

2. The method of edging pile fabrics consisting in bending the base fabric adjacent the edge thereof so as to position the same substantially at right angles to the plane of the base fabric, laying a needle thread along the base of the pile threads at the edge of the fabric and passing loops therein between the pile threads and along the face of the upturned edge portion of the base fabric and thence through the base fabric adjacent the bend therein, and securing said thread loops by olher thread loops which extend along the under face of the base fabric and across the edge thereof where they are secured by the firstnamed threadloops.

3. A sewing machine including a work support, an edge guide, means for guiding a pile fabric with the edge portion thereof upturned and resting against said edge guide, a needle, complemental stilch forming devices cooperating therewith to form overedge stitches, said edge guide being disposed so as to present an upturned edge portion of the pile fabric to the stitching mechanism whereby the concatenated overedge stitches will encircle said upturned edge portion with the needle thread lying along the base of the pile threads at the edge of the fabric and the needle loops formed therein extending through the bend in the fabric portion.

4. A sewing machine including a work support, an edge guide, means for guiding a pile fabric with the edge portion thereof upturned and resting against said edge guide, a needle, complemental stitch forming devices cooperating therewith to form overedge stitches, said edge guide being disposed so as to present an upturned edge portion of the pile fabric to the stitching mechanism whereby the concatenated overedge stitches will encircle said upturned edge portion with the needle thread lying along the base of the pile threads at the edge of the fabric and the needle loops formed therein extending through the bend in the fabric portion, and a gauge plate carried by said edge guide and overhanging the guiding face thereof and limiting the extent to which the edge'portion is upturned.

5. A sewing machine including a work support, an edge guide, means for guiding a pile fabric with the edge portion thereof upturned and resting against said edge guide, a needle, complemental stitch forming devices cooperating therewith to form overedge stitches, said edge guide being disposed so that said upturned edge portion will be encircled by the concatenated overedge stitches and the needle will pass along the pile face of the fabric between the pile threads and close to the upturned edge portion, penetrating said fabric adjacent the bend therein, said guiding means including a presser roller mounted for rotation in a plane parallel to the line of feed and cutting the planeof the work support at an acute angle, and disposed so as to engage said upturned fabric section at the bend therein for holding and guiding the same along the edge guide.

6. A sewing machine including a work support, an edge guide, means for guiding a pile fabric with the edge portion thereof upturned and resting against said edge guide, a needle, complemental stitch forming devices cooperating therewith to form overedge stitches, said edge guide being disposed so that said upturned edge portion will be encircled by the concatenated overedge stitches and the needle will pass along the pile faceof the fabric between the pile threads and close to the upturned edge portion, penetrating said fabric adjacent the bend therein, said edge guide having a stitch finger extending therefrom over which the overedge stitches are formed.

7. A sewing machine including a work support, an edge guide, means for guiding a pile fabric with the edge portion thereof upturned and resting against said edge guide, a needle, complemental stitch forming devices cooperating therewith to form overedge stitches, said edge guide being disposed so that said upturned edge portion will be encircled by the concatenated overedge stitches and the needle will pass along the pile face of the fabric between the pile threads and close to the upturned edge portion,

penetrating said fabric adjacent the bend thereof the base fabric.

KARL MAIER. 

